A face is a code, a shorthand to decipher. Succinct as it is, it is a sizeable piece of information about someone. The human ability to perceive a face is particularly refined and is linked to processes of emotional and cognitive evaluation.
When a face is directly gazing in our direction, the more attractive it is, the more pronounced is a response of gratification in us, with an underlying involvement of brain areas that process reward and a concomitant rush of the neurotransmitter dopamine.
By looking at a face, we involuntarily form inklings about traits and attitudes. One of the immediate features we infer is whether a person is trustworthy or not. Should we yield to them or should we avoid them? Should we dismiss or trust in their intentions? The process is subliminal. Aided by experience and predictions, we produce those rulings unconsciously, within milliseconds. We are so trained that this happens even when we are exposed to a face for a time so short we don’t even realize we have seen it.
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